Process oe enameling



` E. H. WEIL PROCESS OF ENAMELING FiledJan.l 18, 1926 3 Sheets-Sheet 1 Tini.

Edgar H, Weil I que( 84- 1 Oct. i9 E926.

E. H. WEIL PROCESS OF ENAMELING Filed Jan. 18, 1926 l 3 Sheets-Sheet 2 gnvanon Edgar H. Wei) gina/MQ, MJ

E. H. WEIL PROCESS 0F ENAMELING oct. 19, 1926.

C5 Sheets-Sheet 5 Filed Jan. 18, 1926 l Edgar Weit maa Federated Get. 19, i926.

t UNE'@ S'I'AI'ES PATENT FFME.

EDGAR H. WEIL, 0F CLEVELAND, OHIO.

PROCESS 0F Application filed January rihis invention relates to an improved process of vitreous enameling table tops and similar articles having broad faces.

The invention is adapted for use in vitreous enam-eling trays, splashers, broiler pans, roofing tiles and similar articles having relatively large, broad faces thus table tops and the like may be deemed to include any article having broad faces, such as those mentioned above.

In vitreous enameling table tops and the like, it is preferable that all portions of each table top be uniformly heated in order that warpage and buckling of the article be prevented and in order that the enameled surface may be of high quality. It is further desirable that the heating accorded to each table top be of substantially the same kind and degree iny order that the product may be uniform. In addition, dust or other particles should be precluded from attaching to the enameled surfaces and thereby marring-said surfaces, spoiling the gloss of the enamel and causing blemishes therein. During the heating, the table tops and the like should be supported by a relatively small supporting means so that the heat may readily reach all portions of the table top and so that said supporting means may not appreciably mar the enameled surface.

It has been the usual practice to vitrify the enamel on table tops and similar articles in ordinary muflie furnaces provided with large doors whereby substantially the entire interior of the muflie may be exposed. The table tops have usually been horizontally disposed adjacent to the bottom of such muflies on a plurality of metal pins or similar devices, the furnace door closed and the table tops heated to a temperature sufficient to vitrify the enamel thereon. After the Acompletion of the vitrifying process, the door of the furnace has been opened, the entire batch removed as by suitable forks and another batch placed in the furnace, andthe process repeated.

Under the above mentioned conditions of heating the upper broad surfaces of the table tops have'been heated to aV greater degree than the lower surfaces. In other words, the table tops have been non-uniformly heated, whereby warpage was of frequent ENAMELING.

1S, 1926. Serial No. 82,058.

occurrence, thus reducing greatly the utility of the article. Furthermore, particularly during the period when the furnace door has been opened, dust and other fine particles have settled on the surface of the horizontally disposed articles, thereby reducing the gloss and frequently causing gross imperfections in the enameled surface. Blemishes in the enameled surface have' been frequently caused by the pins on which the table tops have beenl supported. Considerable heat loss also results during the period when the furnace door is opened and table tops and the like are being removed from or introduced into the furnace. Additional heat losses are introduced as a result of the cooling o of the article supports when the furnace door is openedl and the absorption of heat by such supports when the door is again closed. It will also be noted that the above mentioned method is discontinuous and partly for this reason has proved unsatisfactory from the standpoint of quantity production.

An object of my invention is to provide a method of vitreous enameling table tops and the like in which the broad faces of such articles are uniformly heated during the vitrifying operation to provide a smooth, uniform enameled surface.

Another object of this invention is to provide a method of vitrifying the enamel on objects having broad surfaces, whereby warpage of such surfaces is prevented.

A further object ofthe invention is to provide a method of supporting table tops and similar articles in a vitrifying furnace whereby marks'or blemishes dueto supporting means are minimized.

Another object of theinvention is to provide a continuous process of vitreous enameling table tops whereby a large production may be secured'and a high quality of product obtained.

Other objects of the invention will be apparent to those skilled in the art from the description of it hereinafter given.

In the drawings:

Figure 1 is a top plan view of a suitable furnace in which my improved process may be carried out;

1 Fig. 2 is asectional view on line 2--2 of Fig. l. showing articles having broad faces,

such as table tops, suitably supported within the vitrifying chamber;

Fig. 3 is an elevation, partly in section, on line 8 3 of Fig. 1; y Y

Fig-1 is a horizontal section on line' 4'-'4 of Fig. 2; and ,y

Fig. 5 is a horizontal section on line 55 of Fig. 2.

My invention contemplates the heating of enameled table tops and the like to a temperature suflicient to` vitrify` the enamel thereon by disposing said table tops intermediate substantially parallel uniformly heatedheat radiating surfaces. The table tops are preferably` supported between' said surfaces by relatively small supporting means so that the heat may readilyreach all pfortOIlS of f the table `top and so that any lemishes fromv supportin means may be reduced to a minimum; T e broad faces-of the table top are preferably disposed facing theparallel and relatively adjacent heat ra.- diatlng portions whereby high heat efficiency is obtained and whereby both` faces of the tabletop are heated substantially uniformly. Thus buckling and warping are substantially prevented and the finished article is given a smooth, flat surface. To meet the needs yof large production, said tabletops may be conveyed` edgewise between substantially parallel and adjacent heat radiating portions whereby each table top will be subjected to uniformheatin'g and the resulting product will be uniform and of high quality. In such continuous process, the heat radiatingr portions are made of s'ufficient extent andthe rate of conveying said articles is made such that the enamelwill be completely vitried when the table top has completed its passagebetween said heat radiating port-ions. y The heat radiating portions between which the table top may be conveyedmay, ofcourse, be of any suitable shape, such as straight, curved or annular,` and said portionsmay extend and the articles may be conveyed vertically, horizontally Vor in any intermediate direction. yMy invention may be carriedoutin a suitable furnace such a's illustrated' in the drawings, in which the furnace proper 1 is disposed in cooperative relation to a conveyor mechanism 2 by means of which mechanism articleshavingbroad faces, such as the table tOPS 3, may be conveyed through the furnace.

1. The furnace 1, which is shownasbeingofannular sector shape, is provided with side walls 4 and' 5, bottom 6, top portions 7 and 8, and stacksshown generally at 9 al l of which members are preferably.. o flbrick, those.: portions which arehexposed to high tlginrerturse beine. preferably of` fire, brick-1 ose of said portions whichare; exposedonly torelatively lowtemperatures may be Otoldeeragbrlk-. 1

Cooperating with the top portions 7 and 8 and spaced from the side walls 4 and 5 and from the bottom 6 are the refractory side walls 10 and il and bottom 12, respectivelyof the muffle chamber 13, 1n which articlesv 3 are heated and enamel thereon vitriied. The top of the chamber 18 is formed in part by lire brick portions of the spaced members 7 and 8, the central portion of said top being sealed by portions of theconveyinff mechanism 2, as will be more fully described hereinafter.

Further interior structural features of the furnace 1 can well be described in connection with the passage of the hot` flue gases therethrough, by means of which gases the chamber' 18 is` heated. Thus, referring particularly to-i'Fig. 4, the fuel for supplying heat to'thef furnace 1 may be gasJ or oi-l entering the` symmetrically Y disposed combustion chambers Illthrough the burners 15.` The sides of each combustion chamber 14 are provided with apertures 16 and 17 whereby the hot gases may Pass into the flue gas chambers 18 or 19.

The flue gas chambers 19 are disposed directly adjacent the chamber wall 11. Above each chamber 19 is disposed a horizontal baille yplate 20. In each combustion chamber, flue gasespassing through apertures 17, therefore, pass rthrough a; chamber 19, aroundthe horizontal baille plate 20, through the narrow passageway 21, into theV upper flue chamber 22, whence the gases pass through duct,23, and Vinto a stack 24 and upwardly and outwardly thereof.

The gases; from ea'ch combustion chamber passing throughapertures 16 enter a flue gas chamber 18, which chamber is of substantially the same height as the chamber lf3, and is disposeddifrcctly adjacent the vitrijfying' chamber walllO. Forming one wall of the chamber 18 isa. vertical baffle 26. Flue gases entering a chamber, 18, therefore, pass upwardly therethrough over the upper edge of the baffle 26, downwardly through the chamber 28, through the substantially horizontal ducts 29 disposed beneath the floor 12 of the vitrifying chamber 13, into. astack 30, andL upwardly and outwardly thereof.

By means of thev horizontal bailes-20 and the vertical bales26 the hot flue gases are forcedjto pass adjacent to practically the entire adjacent areaof the'v walls 1 0 and 11 of the chamber l3,thereby securingy eflicient heating ofthe walls thereof. It will b'e noted. that the 'fine gas: passages, or chambers 18, 19, 21, 22 and 28 are of relatively Smalltransverl'sedimenson, as are alsothcside walls, 1 0 and l11. andthe bottom, 1 2 ofthe. dumber..13..l As resul'tfitherefre, the hefat 0f th liiegases `is readily tralrsrifltted. throughithe.. bottom- 12. and` the. side 10 t@ hzlleavillfyigl chamber 132 andi articles 3 disposed" therein.

Referring to F ig. 4, it will be noted vthat each of the burners may be suitably adjusted tol assist in the regulation of the temperature of the furnace. Additional control of furnace temperature may be obtained by the provision of suitable dampers within the stacks 24 and 30.

Dividing the lower portionof the furnace into two segments is an aperture 31 whiclnas shown, is substantially of the same height as the combustion chambers 14. The aperture 31 provides room for portions of the conveying mechanism 2 and also for burners 15. The endless conveyor mechanism 2, by means of which articles 3 may be disposed wit-hin and removed from the chamber 13, is shown as comprising a vertical rotatable shaft 32 supported by an end thrust bearing 33 and by the structural members 34 and bearing 35. At the upper end of the shaft 32 is mounted a wheel-like structure comprising a hub 36, spokes 37 and rim 33. From the rim 38 aresuspended article supporting means 39, which extend into the chamber 13 through aperture 40. Heat is prevented from escaping from the chamber 13 through the aperture 40 by a suitable closure 41, provided with the substantially vertical members 42. The horizontal portion of the closure 41 is preferably of `refractory material and the vertical runners 42 may be of metal or of refractory material. The vertical portions 42 moveI in sand 43 disposed in the concentric grooves 44 and 45. The' grooves 44 and 45 are completely circular, the portions between the ends of the furnace being bridged by channel members 46 and-47. The motive power for the conveyor mechanism 2 may be provided by a motor 48 disposed outside of the furnace and operatively connected to the shaft 49, which extends through the aperture 31. The shaft 49 drives the shaft 32 through the bevel gears 50 and 51. As shown, the power transmitting portions of the conveyor mechanism 2 are well protected and insulated from the heat of the furnace.

The supports 39 and the articles 3 supported thereby enter and leave the furnace through relatively small apertures 52, which may be partially or entirely closed by doors which are shown as sectionally operable. The effective size of the apertures 52 nia-y thus be made as small as is permissible by the size of the articles 3, thereby minimizinf; heat losses through said apertures.

With apparatus such as herein described,- my improved process may be carried out as follows: An article having broad faces, such as a table top 3, is caused to be supported, preferably outside the furnace, by a supporting or suspending means 39, the table top being preferably so supported as to travel edgewise with its bro-ad faces substantially parallel to the direction of movement. Suspending means 39 is of relatively small mass so that but a small amount of heat will be absorbed thereby and so that substantially all portions of the table top 3 may receive heat directly from the walls of the chamber 13. The suspending means 39 is shown as engaging the table top 3 under a flanged edge thereof. Thus, marks or blemishes left by supporting means are substantially eliminated, the contacting surface between the support 39 and article 3 being preferably made as small as possible.

By rotation of the conveying means 2, the article 3 is moved edgewise throughl one of the narrow apertures 52 into the vitrifying chamber 13 and is conveyed through said chamber 13, the broad faces of the article 3 being disposer during said conveyance relatively adjacent the walls of the chamber 13 and being uniformly subjected to heat from said walls. In a substantially closed chamber, such `as shown, the temperature to which the article 3 is exposed may be very readily controlled and, in addition, dust or other small particles may not readily come in contact with the surfaces to be enameled to dull or mar said surfaces. The temperature of the chamber 13 is so regulated and the speed of movement of the conveying mechanism is such that the enameled surface of an article 3 is completelyvitrified when said article or table top is removed from the chamber 13 through the other aperture 52. During the passage of a table top or the like through the chamber 13, all of the surfaces thereof are uniformly subjected to the vitrifying heat, whereby the vitrified enamel surface produced is of very high uniform quality and whereby any warpage of the table top is substantially eliminated.

The furnace 1 and conveying mechanism 2, as shown, are adapted for the continuous enameling of articles 3. Thus, when the conveyor 2 is in motion, table tops or the like, whose enamel coated surfaces are to be vitrified, may be continuously attached to supporting means 39 and finished articles may be continuously removed therefrom. lith such a continuous process, every article or table top 3 is subjected to the sa-me degree and amount of heat, whereby uniformity of product is assured.

The dimension of the chamber 13 between the side walls 10 and 11 thereof is preferably as small as possible, thereby decreasing the size, of the furnace, increasing the economy of operation, and providing for the ready transfer of heat from the walls of the chamber to the broad faces of the articles to be heated.

The heating chamber 13 may extend in a vertical or other direction rather than horizontally, as shown in the drawings. In such case, the tabletops or similar-articles- 3l may E produced.

Furthermore, it is to b e understood that the particular forms of a paratus shown and described, andthe particular procedureV set forth, are presentedL for pur oses'of explanation and'` illustration and t 'at various modifications of said apparatus'v and procedure can be made withoutv de. arting from my invention as defined in tie appended claims.

Vhat` I claim is:

1. The process of vitrifying enamel on a substantially flat article having broad faces, which comprises supporting said article substantially vertically, and subjecting the pposite faces of the article substantiall uniformly to radiant heat to thereby su lstantially uniformly heat said article and vitrify the enamel thereon.

2. rlhe process of vitrifyingy enamel on a 1 plurality of substantially flat articles having` broad faces, which comprises supporting said articles with the flat faces thereof sub` stantially in vertical position, and subjecting said opposite faces of the articles to radiant if heat to thereby substantially uniformly heat,

the faces of the articles and vitrify the enamel applied to said articles without ap* preciable buckling and warpage of the articles.

3'. rPhe process of vitrifying enamel on Y a plurality of articles having substantially flat, broad surfaces, which comprises supporting the articles with the. fiatsurfa-ces thereof substantially in vertical position and c subjecting the faces ofthe articles to radiant heat -without materially obstructing the radiation of heat to the said faces by the supporting means, thereby heating' said articles substantially uniformly and vitrifying the enamel thereon.

series of substantially flat articles having broadVj faces, which comprises supporting said articles substantially vertically, exposing" said articles to sourcesof'heat and sub jecting the op osite faces of the articles to said sources o heat without obstructing the transmission of heat to said faces of the articles, thereby heating them uniformly and vitrif'yinv said enamel, and conveying the articles` away vfrom they sources of heat'.

5. The process of vitrif in enamel on a series of fiat metallic artic es having broad faces, which comprises supporting saidv articles substantially vertically, continuously conveying said series of articles between sources of radiant heat and subjecting the opposite faces of the articles to substantially the samel amount of heat and thereby unlformly heating them and vitrifying the enamel.v

6. The process of vitrifying enamelona series of substantially flat metallic articles havingsubstantially broad faces, which comprises suspending said articles by their upper marginal portions, continuously conveying said articles consecutively between sources of heat without obstructing the transmission of heat to the faces of the articles and thereby heating substantially all portions of the articles uniformly and vitrifying the enamel, and continuously coneying the articles away from the sources of eat.

7. The process of vitrifying enamel on a series of substantially flat metallic articles having broad faces, which comprises suspendino' said articles substantially vertically with hook suspending means, continuously conveying said articles between sources of heat and heating the faces of the articles substantially uniformly to vitrify the enamel and thereby substantially prevent buckling and warping of the articles and continuously conveyin said articles away from theheat after vitri cation of the enamel.

8. The process of vitrifying enamel on a plurality of articles having substantially flat broad surfaces, which comprises supporting each: of the articles withthe flat broad faces thereof inV substantially vertical position, and subjecting the articles substantially uniformly to radiant heat without materially obstructing the radiation of the heat to the articles' by the supporting means, to vitrify the enamel and thereby substantially prevent bucklingV and warping of the articles.

VIn testimony whereof I affix my signature'.V

EDGAR Hf. WEIL. 

